package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.constant.MessageConstant;
import com.sky.dto.UserLoginDTO;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import org.apache.http.impl.client.HttpClients;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

@Service
public class UserServiceImpl implements UserService {

    //微信服务接口地址
    public static final String WX_LOGIN="https://api.weixin.qq.com/sns/jscode2session";

    @Autowired
    private WeChatProperties weChatProperties;

    @Autowired
    private UserMapper userMapper;

    /**
     * 微信用户登录
     * @param userLoginDTO
     * @return
     */
    public User userLogin(UserLoginDTO userLoginDTO) {
        //调用微信接口服务获取用户唯一标识openid
        String openid = getOpenid(userLoginDTO.getCode());

        //判断openid是否为空，为空则登录失败，抛出业务异常
        if(openid == null){
            throw new LoginFailedException(MessageConstant.LOGIN_FAILED);//登录失败
        }
        //如果不为空，查询数据库判断当前用户是否为新用户
        User user = userMapper.selectByOpenId(openid);
        //如果是新用户，插入数据库
        if(user == null){
             user = User.builder()
                    .openid(openid)
                    .createTime(LocalDateTime.now())
                    .build();
            userMapper.insertUser(user);
        }
        //返回这个用户对象
        return user;
    }

    /**
     * 调用微信接口服务获取用户唯一标识openid
     * @param code
     * @return
     */
    private String getOpenid(String code){
        //https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-login/code2Session.html小程序开发者文档的地址

        Map<String, String> map = new HashMap<>();//map里封装的就是请求参数
        map.put("appid",weChatProperties.getAppid());
        map.put("secret",weChatProperties.getSecret());
        map.put("js_code",code);
        map.put("grant_type","authorization_code");
        String json = HttpClientUtil.doGet(WX_LOGIN, map);//返回的是一个json字符串

        JSONObject jsonObject = JSON.parseObject(json);
        String openid = jsonObject.getString("openid");
        return openid;
    }
}
